The purpose of this article is to report on the long-term clinical evaluation of patients treated with dental implants. A total of 106 implants were placed in 34 patients and restored with fixed partial dentures and overdentures. The 12-year cumulative implant survival and success rates were 95.2% and 90.2%, respectively. Probing depths around mandibular implants were significantly lower than those around maxillary implants (P .05). The cumulative implant success rate in nonsmokers was 97.7%, but this dropped to 75.81% in smokers. Also, patients rehabilitated with implant-supported overdentures had more peri-implant tissue inflammation than patients with fixed prostheses.